In the field of orthopaedics, prostheses have been devised for the replacement of many joints in the body. Common applications include hip, shoulder, and knee joint replacements. Such total joint replacement has become a commonplace and effective treatment for the incapacitating pain of arthritis for example.
A large joint prosthesis, such as for a hip or shoulder, typically includes a head that serves as the ball joint and a stem having a shaft that is inserted into a long bone to fix the prosthesis in place. The head and stem and the methods of attaching the head to the stem will differ depending on the type of joint to be replaced and the particular prosthesis as is known in the art.
In a conventional arthroplasty procedure, a prosthesis is first selected and assembled. In surgery, an incision is made for access to the long bone, which is prepared for receipt of the stem with the use of various broaches, rasps, and reamers to ensure a proper fit. The stem is inserted into the long bone and fixed into place with cement, screws, or other means known in the art.
On occasion, the long bone adjacent a prosthesis fractures, requiring treatment. Were the prosthesis not in place, such a fracture would conventionally be treated by the insertion of a intramedullary device, such as an intramedullary nail placed across the fracture area and used to fix the bone into place. However, when a joint prosthesis is in place, access to the point of the fracture is more difficult. In such a case, a joint revision may be required, removing the artificial joint and replacing it with another prosthesis that includes a longer stem traversing the fracture. However, such a joint revision is a complicated procedure and is not an ideal methodology. Therefore, a makeshift internal fixation may be performed that attempts to treat the fracture with external devices such as plates, screws, and wires. Another approach to treating the fracture and avoiding joint revision is to utilize bed rest and traction.
It would be advantageous to have a joint prosthesis that is designed to anticipate the possibility of a periarticular fracture above or below the prosthesis and allow effective treatment of the fracture without requiring removal of the entire artificial joint. It would be further advantageous if a joint prosthesis were designed to allow the replacement of the shaft portion of the stem with a different shaft after the prosthesis has been implanted.
It would be desirable to provide a system and/or method that provides one or more of these or other advantageous features. Other features and advantages will be made apparent from the present specification. The teachings disclosed extend to those embodiments that fall within the scope of the appended claims, regardless of whether they accomplish one or more of the aforementioned needs.